ERS | monograph Guest Editors Marko Z. Nikolić Marko Z. Nikolić is a UKRI (UK Research and Innovation) Innovation/Rutherford Fellow at University College London (London, UK) as part of the UK Regenerative Medicine Platform. After completing a Wellcome PhD Programme for Clinicians and a Clinical Lectureship at the Gurdon Institute in Cambridge (UK) with Emma Rawlins, he moved to University College London to set up his independent research group. He is interested in developmental and stem cell biology in the context of lung regeneration, while also contributing to the Human Cell Atlas as a member of the HCA Lung Biological Network. He continues his clinical commitments as an Honorary Consultant in Respiratory Medicine at Royal Papworth (Cambridge, UK), Cambridge University Hospitals and University College London Hospitals Foundation Trusts. Brigid L.M. Hogan Brigid L.M. Hogan began her career in the UK as a developmental biologist where she made seminal discoveries about the genetic and cellular mechanisms controlling the formation of organ systems in the mammalian embryo. After moving to the USA in 1988, she began to focus more on the lung after initially being captivated by its branching morphogenesis. Her lab was among the first to use genetically engineered mice to identify and study stem and progenitor cells in the adult lung and their role in tissue maintenance and repair after injury. Her lab also developed some of the first lung organoids. Many of her trainees are now conducting innovative and translational research in the field of lung biology. From 2002 to 2019, Brigid was George Barth Geller Professor and Chair of the Department of Cell Biology at Duke University (Durham, NC, USA). She is a member of the National Academy of Medicine and the National Academy of Sciences in the USA and a Fellow of the Royal Society of London. Copyright ©ERS 2021. Print ISBN: 978-1-84984-133-7. Online ISBN: 978-1-84984-134-4. Print ISSN: 2312-508X. Online ISSN: 2312-5098. viii https://doi.org/10.1183/2312508X.10004221